8046246: the constantPoolCacheOopDesc::adjust_method_entries() used in RedefineClasses does not scale

Optimize the adjust_method_entries functions by using the orig_method_idnum() function

Reviewed-by: coleenp, dcubed

hotspot/src/share/vm/classfile/defaultMethods.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1091,6 +1091,7 @@ static void merge_in_new_methods(InstanceKlass* klass,
     }
     // update idnum for new location
     merged_methods->at(i)->set_method_idnum(i);
+    merged_methods->at(i)->set_orig_method_idnum(i);
   }
 
   // Verify correct order

hotspot/src/share/vm/oops/constMethod.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -215,6 +215,7 @@ private:
   u2                _max_stack;                  // Maximum number of entries on the expression stack
   u2                _max_locals;                 // Number of local variables used by this method
   u2                _size_of_parameters;         // size of the parameter block (receiver + arguments) in words
+  u2                _orig_method_idnum;          // Original unique identification number for the method
 
   // Constructor
   ConstMethod(int byte_code_size,
@@ -473,6 +474,9 @@ public:
   u2 method_idnum() const                        { return _method_idnum; }
   void set_method_idnum(u2 idnum)                { _method_idnum = idnum; }
 
+  u2 orig_method_idnum() const                   { return _orig_method_idnum; }
+  void set_orig_method_idnum(u2 idnum)           { _orig_method_idnum = idnum; }
+
   // max stack
   int  max_stack() const                         { return _max_stack; }
   void set_max_stack(int size)                   { _max_stack = size; }

hotspot/src/share/vm/oops/cpCache.cpp

@@ -455,7 +455,6 @@ bool ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
           new_method->name()->as_C_string(),
           new_method->signature()->as_C_string()));
       }
-
       return true;
     }
 
@@ -483,7 +482,6 @@ bool ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
         new_method->name()->as_C_string(),
         new_method->signature()->as_C_string()));
     }
-
     return true;
   }
 
@@ -510,36 +508,33 @@ bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
           (!f1_as_method()->is_old() && !f1_as_method()->is_obsolete())));
 }
 
-bool ConstantPoolCacheEntry::is_interesting_method_entry(Klass* k) {
+Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
   if (!is_method_entry()) {
     // not a method entry so not interesting by default
-    return false;
+    return NULL;
   }
-
   Method* m = NULL;
   if (is_vfinal()) {
     // virtual and final so _f2 contains method ptr instead of vtable index
     m = f2_as_vfinal_method();
   } else if (is_f1_null()) {
     // NULL _f1 means this is a virtual entry so also not interesting
-    return false;
+    return NULL;
   } else {
     if (!(_f1->is_method())) {
       // _f1 can also contain a Klass* for an interface
-      return false;
+      return NULL;
     }
     m = f1_as_method();
   }
-
   assert(m != NULL && m->is_method(), "sanity check");
   if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
     // robustness for above sanity checks or method is not in
     // the interesting class
-    return false;
+    return NULL;
   }
-
   // the method is in the interesting class so the entry is interesting
-  return true;
+  return m;
 }
 #endif // INCLUDE_JVMTI
 
@@ -627,7 +622,7 @@ void ConstantPoolCache::adjust_method_entries(Method** old_methods, Method** new
   Klass* old_holder = old_methods[0]->method_holder();
 
   for (int i = 0; i < length(); i++) {
-    if (!entry_at(i)->is_interesting_method_entry(old_holder)) {
+    if (entry_at(i)->get_interesting_method_entry(old_holder) == NULL) {
       // skip uninteresting methods
       continue;
     }
@@ -651,10 +646,33 @@ void ConstantPoolCache::adjust_method_entries(Method** old_methods, Method** new
   }
 }
 
+// If any entry of this ConstantPoolCache points to any of
+// old_methods, replace it with the corresponding new_method.
+void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
+  for (int i = 0; i < length(); i++) {
+    ConstantPoolCacheEntry* entry = entry_at(i);
+    Method* old_method = entry->get_interesting_method_entry(holder);
+    if (old_method == NULL || !old_method->is_old()) {
+      continue; // skip uninteresting entries
+    }
+    if (old_method->is_deleted()) {
+      // clean up entries with deleted methods
+      entry->initialize_entry(entry->constant_pool_index());
+      continue;
+    }
+    Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
+
+    assert(new_method != NULL, "method_with_idnum() should not be NULL");
+    assert(old_method != new_method, "sanity check");
+
+    entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
+  }
+}
+
 // the constant pool cache should never contain old or obsolete methods
 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
   for (int i = 1; i < length(); i++) {
-    if (entry_at(i)->is_interesting_method_entry(NULL) &&
+    if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
         !entry_at(i)->check_no_old_or_obsolete_entries()) {
       return false;
     }
@@ -664,7 +682,7 @@ bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
 
 void ConstantPoolCache::dump_cache() {
   for (int i = 1; i < length(); i++) {
-    if (entry_at(i)->is_interesting_method_entry(NULL)) {
+    if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
       entry_at(i)->print(tty, i);
     }
   }

hotspot/src/share/vm/oops/cpCache.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -381,7 +381,7 @@ class ConstantPoolCacheEntry VALUE_OBJ_CLASS_SPEC {
   bool adjust_method_entry(Method* old_method, Method* new_method,
          bool* trace_name_printed);
   bool check_no_old_or_obsolete_entries();
-  bool is_interesting_method_entry(Klass* k);
+  Method* get_interesting_method_entry(Klass* k);
 #endif // INCLUDE_JVMTI
 
   // Debugging & Printing
@@ -479,6 +479,7 @@ class ConstantPoolCache: public MetaspaceObj {
   // group don't print the klass name.
   void adjust_method_entries(Method** old_methods, Method** new_methods,
                              int methods_length, bool* trace_name_printed);
+  void adjust_method_entries(InstanceKlass* holder, bool* trace_name_printed);
   bool check_no_old_or_obsolete_entries();
   void dump_cache();
 #endif // INCLUDE_JVMTI

hotspot/src/share/vm/oops/instanceKlass.cpp

@@ -2793,16 +2793,21 @@ Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
 // not yet in the vtable due to concurrent subclass define and superinterface
 // redefinition
 // Note: those in the vtable, should have been updated via adjust_method_entries
-void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
+void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
-                                           int methods_length, bool* trace_name_printed) {
   // search the default_methods for uses of either obsolete or EMCP methods
   if (default_methods() != NULL) {
-    for (int j = 0; j < methods_length; j++) {
-      Method* old_method = old_methods[j];
-      Method* new_method = new_methods[j];
-
     for (int index = 0; index < default_methods()->length(); index ++) {
-        if (default_methods()->at(index) == old_method) {
+      Method* old_method = default_methods()->at(index);
+      if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
+        continue; // skip uninteresting entries
+      }
+      assert(!old_method->is_deleted(), "default methods may not be deleted");
+
+      Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
+
+      assert(new_method != NULL, "method_with_idnum() should not be NULL");
+      assert(old_method != new_method, "sanity check");
+
       default_methods()->at_put(index, new_method);
       if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
         if (!(*trace_name_printed)) {
@@ -2819,8 +2824,6 @@ void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_me
     }
   }
 }
-  }
-}
 #endif // INCLUDE_JVMTI
 
 // On-stack replacement stuff

hotspot/src/share/vm/oops/instanceKlass.hpp

@@ -937,8 +937,7 @@ class InstanceKlass: public Klass {
   Method* method_at_itable(Klass* holder, int index, TRAPS);
 
 #if INCLUDE_JVMTI
-  void adjust_default_methods(Method** old_methods, Method** new_methods,
+  void adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed);
-                              int methods_length, bool* trace_name_printed);
 #endif // INCLUDE_JVMTI
 
   // Garbage collection

hotspot/src/share/vm/oops/klassVtable.cpp

@@ -864,20 +864,22 @@ bool klassVtable::adjust_default_method(int vtable_index, Method* old_method, Me
   }
   return updated;
 }
-void klassVtable::adjust_method_entries(Method** old_methods, Method** new_methods,
-                                        int methods_length, bool * trace_name_printed) {
-  // search the vtable for uses of either obsolete or EMCP methods
-  for (int j = 0; j < methods_length; j++) {
-    Method* old_method = old_methods[j];
-    Method* new_method = new_methods[j];
 
-    // In the vast majority of cases we could get the vtable index
+// search the vtable for uses of either obsolete or EMCP methods
-    // by using:  old_method->vtable_index()
+void klassVtable::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
-    // However, there are rare cases, eg. sun.awt.X11.XDecoratedPeer.getX()
+  int prn_enabled = 0;
-    // in sun.awt.X11.XFramePeer where methods occur more than once in the
-    // vtable, so, alas, we must do an exhaustive search.
   for (int index = 0; index < length(); index++) {
-      if (unchecked_method_at(index) == old_method) {
+    Method* old_method = unchecked_method_at(index);
+    if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
+      continue; // skip uninteresting entries
+    }
+    assert(!old_method->is_deleted(), "vtable methods may not be deleted");
+
+    Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
+
+    assert(new_method != NULL, "method_with_idnum() should not be NULL");
+    assert(old_method != new_method, "sanity check");
+
     put_method_at(new_method, index);
     // For default methods, need to update the _default_methods array
     // which can only have one method entry for a given signature
@@ -900,9 +902,6 @@ void klassVtable::adjust_method_entries(Method** old_methods, Method** new_metho
                             new_method->signature()->as_C_string(),
                             updated_default ? "true" : "false"));
     }
-        // cannot 'break' here; see for-loop comment above.
-      }
-    }
   }
 }
 
@@ -1194,20 +1193,22 @@ void klassItable::initialize_with_method(Method* m) {
 }
 
 #if INCLUDE_JVMTI
-void klassItable::adjust_method_entries(Method** old_methods, Method** new_methods,
-                                        int methods_length, bool * trace_name_printed) {
 // search the itable for uses of either obsolete or EMCP methods
-  for (int j = 0; j < methods_length; j++) {
+void klassItable::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
-    Method* old_method = old_methods[j];
+
-    Method* new_method = new_methods[j];
+  itableMethodEntry* ime = method_entry(0);
-    itableMethodEntry* ime = method_entry(0);
+  for (int i = 0; i < _size_method_table; i++, ime++) {
+    Method* old_method = ime->method();
+    if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
+      continue; // skip uninteresting entries
+    }
+    assert(!old_method->is_deleted(), "itable methods may not be deleted");
+
+    Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
+
+    assert(new_method != NULL, "method_with_idnum() should not be NULL");
+    assert(old_method != new_method, "sanity check");
 
-    // The itable can describe more than one interface and the same
-    // method signature can be specified by more than one interface.
-    // This means we have to do an exhaustive search to find all the
-    // old_method references.
-    for (int i = 0; i < _size_method_table; i++) {
-      if (ime->method() == old_method) {
     ime->initialize(new_method);
 
     if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
@@ -1222,10 +1223,6 @@ void klassItable::adjust_method_entries(Method** old_methods, Method** new_metho
         new_method->name()->as_C_string(),
         new_method->signature()->as_C_string()));
     }
-        // cannot 'break' here; see for-loop comment above.
-      }
-      ime++;
-    }
   }
 }
 

hotspot/src/share/vm/oops/klassVtable.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -98,8 +98,7 @@ class klassVtable : public ResourceObj {
   // printed the klass name so that other routines in the adjust_*
   // group don't print the klass name.
   bool adjust_default_method(int vtable_index, Method* old_method, Method* new_method);
-  void adjust_method_entries(Method** old_methods, Method** new_methods,
+  void adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed);
-                             int methods_length, bool * trace_name_printed);
   bool check_no_old_or_obsolete_entries();
   void dump_vtable();
 #endif // INCLUDE_JVMTI
@@ -288,8 +287,7 @@ class klassItable : public ResourceObj {
   // trace_name_printed is set to true if the current call has
   // printed the klass name so that other routines in the adjust_*
   // group don't print the klass name.
-  void adjust_method_entries(Method** old_methods, Method** new_methods,
+  void adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed);
-                             int methods_length, bool * trace_name_printed);
   bool check_no_old_or_obsolete_entries();
   void dump_itable();
 #endif // INCLUDE_JVMTI

hotspot/src/share/vm/oops/method.cpp

@@ -1450,6 +1450,7 @@ void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idn
       for (int i = 0; i < length; i++) {
         Method* m = methods->at(i);
         m->set_method_idnum(i);
+        m->set_orig_method_idnum(i);
       }
     }
   }

hotspot/src/share/vm/oops/method.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -233,6 +233,9 @@ class Method : public Metadata {
   u2 method_idnum() const           { return constMethod()->method_idnum(); }
   void set_method_idnum(u2 idnum)   { constMethod()->set_method_idnum(idnum); }
 
+  u2 orig_method_idnum() const           { return constMethod()->orig_method_idnum(); }
+  void set_orig_method_idnum(u2 idnum)   { constMethod()->set_orig_method_idnum(idnum); }
+
   // code size
   int code_size() const                  { return constMethod()->code_size(); }
 

hotspot/src/share/vm/prims/jvmtiRedefineClasses.cpp

@@ -782,9 +782,13 @@ jvmtiError VM_RedefineClasses::compare_and_normalize_class_versions(
           Method* idnum_owner = scratch_class->method_with_idnum(old_num);
           if (idnum_owner != NULL) {
             // There is already a method assigned this idnum -- switch them
+            // Take current and original idnum from the new_method
             idnum_owner->set_method_idnum(new_num);
+            idnum_owner->set_orig_method_idnum(k_new_method->orig_method_idnum());
           }
+          // Take current and original idnum from the old_method
           k_new_method->set_method_idnum(old_num);
+          k_new_method->set_orig_method_idnum(k_old_method->orig_method_idnum());
           if (thread->has_pending_exception()) {
             return JVMTI_ERROR_OUT_OF_MEMORY;
           }
@@ -817,9 +821,12 @@ jvmtiError VM_RedefineClasses::compare_and_normalize_class_versions(
         Method* idnum_owner = scratch_class->method_with_idnum(num);
         if (idnum_owner != NULL) {
           // There is already a method assigned this idnum -- switch them
+          // Take current and original idnum from the new_method
           idnum_owner->set_method_idnum(new_num);
+          idnum_owner->set_orig_method_idnum(k_new_method->orig_method_idnum());
         }
         k_new_method->set_method_idnum(num);
+        k_new_method->set_orig_method_idnum(num);
         if (thread->has_pending_exception()) {
           return JVMTI_ERROR_OUT_OF_MEMORY;
         }
@@ -3327,6 +3334,7 @@ void VM_RedefineClasses::AdjustCpoolCacheAndVtable::do_klass(Klass* k) {
   // This is a very busy routine. We don't want too much tracing
   // printed out.
   bool trace_name_printed = false;
+  InstanceKlass *the_class = InstanceKlass::cast(_the_class_oop);
 
   // Very noisy: only enable this call if you are trying to determine
   // that a specific class gets found by this routine.
@@ -3338,10 +3346,8 @@ void VM_RedefineClasses::AdjustCpoolCacheAndVtable::do_klass(Klass* k) {
   // If the class being redefined is java.lang.Object, we need to fix all
   // array class vtables also
   if (k->oop_is_array() && _the_class_oop == SystemDictionary::Object_klass()) {
-    k->vtable()->adjust_method_entries(_matching_old_methods,
+    k->vtable()->adjust_method_entries(the_class, &trace_name_printed);
-                                       _matching_new_methods,
+
-                                       _matching_methods_length,
-                                       &trace_name_printed);
   } else if (k->oop_is_instance()) {
     HandleMark hm(_thread);
     InstanceKlass *ik = InstanceKlass::cast(k);
@@ -3383,14 +3389,9 @@ void VM_RedefineClasses::AdjustCpoolCacheAndVtable::do_klass(Klass* k) {
         || ik->is_subtype_of(_the_class_oop))) {
       // ik->vtable() creates a wrapper object; rm cleans it up
       ResourceMark rm(_thread);
-      ik->vtable()->adjust_method_entries(_matching_old_methods,
+
-                                          _matching_new_methods,
+      ik->vtable()->adjust_method_entries(the_class, &trace_name_printed);
-                                          _matching_methods_length,
+      ik->adjust_default_methods(the_class, &trace_name_printed);
-                                          &trace_name_printed);
-      ik->adjust_default_methods(_matching_old_methods,
-                                 _matching_new_methods,
-                                 _matching_methods_length,
-                                 &trace_name_printed);
     }
 
     // If the current class has an itable and we are either redefining an
@@ -3405,10 +3406,8 @@ void VM_RedefineClasses::AdjustCpoolCacheAndVtable::do_klass(Klass* k) {
         || ik->is_subclass_of(_the_class_oop))) {
       // ik->itable() creates a wrapper object; rm cleans it up
       ResourceMark rm(_thread);
-      ik->itable()->adjust_method_entries(_matching_old_methods,
+
-                                          _matching_new_methods,
+      ik->itable()->adjust_method_entries(the_class, &trace_name_printed);
-                                          _matching_methods_length,
-                                          &trace_name_printed);
     }
 
     // The constant pools in other classes (other_cp) can refer to
@@ -3432,10 +3431,7 @@ void VM_RedefineClasses::AdjustCpoolCacheAndVtable::do_klass(Klass* k) {
       other_cp = constantPoolHandle(ik->constants());
       cp_cache = other_cp->cache();
       if (cp_cache != NULL) {
-        cp_cache->adjust_method_entries(_matching_old_methods,
+        cp_cache->adjust_method_entries(the_class, &trace_name_printed);
-                                        _matching_new_methods,
-                                        _matching_methods_length,
-                                        &trace_name_printed);
       }
     }
 
@@ -3578,6 +3574,7 @@ int VM_RedefineClasses::check_methods_and_mark_as_obsolete() {
 
       // obsolete methods need a unique idnum so they become new entries in
       // the jmethodID cache in InstanceKlass
+      assert(old_method->method_idnum() == new_method->method_idnum(), "must match");
       u2 num = InstanceKlass::cast(_the_class_oop)->next_method_idnum();
       if (num != ConstMethod::UNSET_IDNUM) {
         old_method->set_method_idnum(num);